{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,25]],"date-time":"2026-09-25T01:28:49Z","timestamp":1790299729150,"version":"4.1.0"},"reference-count":32,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2016,10,26]],"date-time":"2016-10-26T00:00:00Z","timestamp":1477440000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>An aortic aneurysm is a lethal arterial disease that mainly occurs in the thoracic and abdominal regions of the aorta. Thoracic aortic aneurysms are prevalent in the root\/ascending parts of the aorta and can lead to aortic rupture resulting in the sudden death of patients. Understanding the biomechanical and histopathological changes associated with ascending thoracic aortic aneurysms (ATAAs), this study investigates the mechanical properties of the aorta during strip-biaxial tensile cycles. The loss factor\u2014defined as the ratio of dissipated energy to the energy absorbed during a tensile cycle\u2014the incremental modulus, and their anisotropy indexes were compared with the media fiber compositions for aneurysmal (n = 26) and control (n = 4) human ascending aortas. The aneurysmal aortas were categorized into the aortas with bicuspid aortic valves (BAV) and tricuspid aortic valves (TAV). The strip-biaxial loss factor correlates well with the diameter of the aortas with BAV and TAV (for the axial direction, respectively, R2 = 0.71, p = 0.0022 and R2 = 0.54, p = 0.0096). The loss factor increases significantly with patients\u2019 age in the BAV group (for the axial direction: R2 = 0.45, p = 0.0164). The loss factor is isotropic for all TAV quadrants, whereas it is on average only isotropic in the anterior and outer curvature regions of the BAV group. The results suggest that loss factor may be a useful surrogate measure to describe the histopathology of aneurysmal tissue and to demonstrate the differences between ATAAs with the BAV and TAV.<\/jats:p>","DOI":"10.3390\/ma9110867","type":"journal-article","created":{"date-parts":[[2016,10,26]],"date-time":"2016-10-26T10:12:01Z","timestamp":1477476721000},"page":"867","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["Investigation on the Regional Loss Factor and Its Anisotropy for Aortic Aneurysms"],"prefix":"10.3390","volume":"9","author":[{"given":"Nastaran","family":"Shahmansouri","sequence":"first","affiliation":[{"name":"Department of Mechanical Engineering, McGill University, Montreal, QC H3A 0C3, Canada"},{"name":"Research Center, Montreal Heart Institute, Montreal, QC H1T 1C8, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mohammed","family":"Alreshidan","sequence":"additional","affiliation":[{"name":"Division of Cardiac Surgery, Royal Victoria Hospital, Montreal, Montreal, QC H4A 3J1, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alexander","family":"Emmott","sequence":"additional","affiliation":[{"name":"Research Center, Montreal Heart Institute, Montreal, QC H1T 1C8, Canada"},{"name":"Department of Chemical Engineering, McGill University, Montreal, QC H3A 2B2, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kevin","family":"Lachapelle","sequence":"additional","affiliation":[{"name":"Division of Cardiac Surgery, Royal Victoria Hospital, Montreal, Montreal, QC H4A 3J1, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Isma\u00efl","family":"El-Hamamsy","sequence":"additional","affiliation":[{"name":"Research Center, Montreal Heart Institute, Montreal, QC H1T 1C8, Canada"},{"name":"Division of Cardiac Surgery, Montreal Heart Institute, Universit\u00e9 de Montr\u00e9al, Montreal, QC H1T 1C8, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Raymond","family":"Cartier","sequence":"additional","affiliation":[{"name":"Research Center, Montreal Heart Institute, Montreal, QC H1T 1C8, Canada"},{"name":"Division of Cardiac Surgery, Montreal Heart Institute, Universit\u00e9 de Montr\u00e9al, Montreal, QC H1T 1C8, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Richard","family":"Leask","sequence":"additional","affiliation":[{"name":"Research Center, Montreal Heart Institute, Montreal, QC H1T 1C8, Canada"},{"name":"Department of Chemical Engineering, McGill University, Montreal, QC H3A 2B2, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rosaire","family":"Mongrain","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, McGill University, Montreal, QC H3A 0C3, Canada"},{"name":"Research Center, Montreal Heart Institute, Montreal, QC H1T 1C8, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2016,10,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"841","DOI":"10.1016\/j.jacc.2009.08.084","article-title":"Thoracic Aortic Aneurysm: Clinically Pertinent Controversies and Uncertainties","volume":"55","author":"Elefteriades","year":"2010","journal-title":"J. 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Biomech."}],"container-title":["Materials"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1996-1944\/9\/11\/867\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T19:34:02Z","timestamp":1760211242000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1996-1944\/9\/11\/867"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2016,10,26]]},"references-count":32,"journal-issue":{"issue":"11","published-online":{"date-parts":[[2016,11]]}},"alternative-id":["ma9110867"],"URL":"https:\/\/doi.org\/10.3390\/ma9110867","relation":{},"ISSN":["1996-1944"],"issn-type":[{"value":"1996-1944","type":"electronic"}],"subject":[],"published":{"date-parts":[[2016,10,26]]}}}